Migrate aslr test to gtest.

Create tests which test the values of mmap_rnd_bits, and
mmap_rnd_compat_bits, if applicable, and verify that the address space
is randomized as expected given the provided values.

Also add a pair of tests to CTS that enforce that the observed entropy
is at least as high as a designated value.  That value will start as our
default value, which also corresponds to the maximum value of some
configurations.

Packaging of executables along with a nativetest suite is not supported,
so add a dummy nativetest suite, scrape_mmap_addr, which ensure that the
executables are present along with the given tests at predictable
locations.

Bug: 26512380
Change-Id: Ib1202984f9b98c503b8d3bc2c2248a9d06940845

1 files changed, 77 insertions, 0 deletions

diff --git a/tests/kernel.config/aslr_test.h b/tests/kernel.config/aslr_test.h
new file mode 100644
index 00000000..355a62a5
--- /dev/null
+++ b/tests/kernel.config/aslr_test.h
@@ -0,0 +1,77 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef ASLR_TEST_H
+#define ASLR_TEST_H
+
+#include <cmath>
+#include <errno.h>
+#include <fstream>
+#include <iostream>
+#include <stdint.h>
+#include <string>
+#include <sys/wait.h>
+#include <unistd.h>
+#include <unordered_set>
+
+#include <gtest/gtest.h>
+
+#define MAX_ADDR_LEN 256
+
+#define PROCFS_PATH "/proc/sys/vm/mmap_rnd_bits"
+#define PROCFS_COMPAT_PATH "/proc/sys/vm/mmap_rnd_compat_bits"
+
+#define SCRAPE_PATH_64 "/data/nativetest64/scrape_mmap_addr/scrape_mmap_addr"
+#define SCRAPE_PATH_32 "/data/nativetest/scrape_mmap_addr/scrape_mmap_addr"
+#define SCRAPE_LIB_64 "/system/bin/linker64"
+#define SCRAPE_LIB_32 "/system/bin/linker"
+
+class AslrMmapTest : public ::testing::Test {
+  protected:
+    static void SetUpTestCase();
+    static const char *path;
+    static const char *lib;
+    static unsigned int def, min, max;
+    static bool compat, user32;
+    static unsigned int def_cmpt, min_cmpt, max_cmpt;
+
+    void TearDown();
+};
+
+/*
+ * gets the current mmap_rnd_bits value. requires root.
+ */
+unsigned int get_mmap_rnd_bits(bool compat);
+
+/*
+ * sets the corresponding mmap_rnd_bits variable, returns false if couldn't
+ * change. requires root.
+ */
+bool set_mmap_rnd_bits(unsigned int new_val, bool compat);
+
+/*
+ * scrape_addr - get the raw starting address from /proc/child_pid/mmaps
+ */
+std::string scrape_addr(const char *exec_name, const char *lib_match);
+
+/*
+ * forks off sample_size processes and records the starting address of the
+ * indicated library as reported by exec_name.  Reports entropy observed among
+ * recorded samples.
+ */
+unsigned int calc_mmap_entropy(const char *exec_name, const char *lib_match, size_t samp_sz);
+
+#endif //ASLR_TEST_H